Mishra and Yalkowsky

Method of Mishra and Yalkowsky Mishra and Yalkowsky [6] have discussed the application of the method of Mackay (eq. 7.2.1). Based on the data set used by Mackay et al. [5] they derived the following model  

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Chain-Length Method of Mishra and Yalkowsky The method of Mishra and Yalkowsky [11] is a modification of Trouton s rule for long-chain hydrocarbons, including alkanes, alkenes, cyclopentanes, cyclohexanes, and alkylbenzenes. The relationship is... 

The Kp values (Grain, 1990), which range between 0.97 and 1.38, were derived for monofunctional compounds, but they also apply to polyfunctional compounds if the respective highest value is used. For compound classes not considered, a default value of 1.06 is recommended, but the lack or ambiguity of specific values for some classes may result in erroneous estimates. Models 1-4 are equally well suited for liquid compounds, whereas for solids methods 3 and 4 are preferable. The fifth function (Mackay et aL, 1982), in contrast to models 1, is only applicable for liquid and solid hydrocarbons and halogenated hydrocarbons these compound classes are also covered by the other models. Model 5 has been revised on a thermodynamic basis by Mishra and Yalkowsky (1991), who introduced terms on the rotational symmetry and the conformational flexibility of the molecules to extend the application range to diverse liquids and solids. Calculations based on the free energy of solvation and the contact surface area (Schiitirmann, 1995) have been limited to substituted benzenes. 

Myrdal, P.B., G.H. Ward, R.-M. Dannenfelser, D. Mishra, and S.H. Yalkowsky. 1992. AQUAFAC 1 Aqueous Functional Group Activity Coefficients Application to Hydrocarbons. Chemosphere 24, 1047-1061. 

Myrdal, P.B., Ward, G.H., Dannenfelser, R.M., Mishra, D., and Yalkowsky, S.H., AQUAFAC aqueous functional group activity coefficients application to hydrocarbons, Chemosphere, 24 1047-1061, 1992. 

This model is based on Sw data spanning 5 log units. Nirmalakhandan and Speece [36,37] discuss the model s validity and robustness in detail. They performed a test using experimental Sw data for esters, ethers, and aldehydes that were not included in the training set. They noted reasonably good agreement between experimental and estimated data for the test set and indicated that eq. 11.5.4 is applicable to dialkyl ethers, alkanals, and alkyl alkanoates, but not for ketones, amines, PAHs, and PCBs. Nirmalakhandan and Speece [37] expanded the model above for the PAHs, PCBs, and PCDDs. However, their model has been criticized by Yalkowsky and Mishra for incorrect and omitted data [38]. The revised model is [38]... 

Yalkowsky, S. H. 1999Solubility and solubilization in aqueous media. New York Oxford University Press. Young, T. J., S. Mawson, K. P. Johnston, I. B. Henriksen, G. W. Pace, and A. K. Mishra. 2000. Rapid expansion from supercritical to aqueous solution to produce submicron suspensions of water-insoluble drugs. Biotechnol. Prog.16 402-407. 

Because is not directly accessible, the total enthalpy change may be aggregated from the individual processes involved (Yalkowsky and Mishra, 1991), which include the heat capacities and enthalpies of melting and boiling as well as the melting point (TJ and the boiling point (7 ), with the melt-... 

Yalkowsky, S. H. and Mishra, D. S. (1991) Vapor pressure estimations for organic compounds. Sci. Total Environ., 109/110, 243-50. 

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